Synthesizing Highly Regular Single-Layer Alkynyl–Silver Networks at the Micrometer Scale via Gas-Mediated Surface Reaction

Extended organometallic honeycomb alkynyl–silver networks have been synthesized on a noble metal surface under ultrahigh vacuum conditions via a gas-mediated surface reaction protocol. Specifically, the controlled exposure to molecular oxygen efficiently deprotonates terminal alkyne moieties of 1,3,5-tris­(4-ethynylphenyl)­benzene (Ext-TEB) precursors adsorbed on Ag(111). At T_sub = 200 K, this O₂-mediated reaction pathway features high chemoselectivity without poisoning the surface. Through mild annealing to 375 K, long-range ordered alkynyl–silver networks incorporating substrate atoms evolve, featuring Ag-bis-acetylide motifs, high structural quality and a regular arrangement of nanopores with a van der Waals cavity of ≈8.3 nm².